The present invention relates to an acousto-electrical device capable of storing information in analog form, at any point of a surface, and of processing this information in different ways, such as Fourier's transformation for example.
Different acousto-electrical devices have already been used for storing and processing information. They are generally formed by a piezoelectric substrate and a semi-conductor substrate placed face to face; acoustic waves, also called elastic waves, are generated at the surface of the piezoelectric substrate; their interactions create spatially differentiated areas which represent them and which are stored in the semi-conductor substrate. Other acoustic waves are subsequently generated at the surface of the piezoelectric substrate and interact with the stored information, thus achieving processing of the information borne by the elastic waves, such as correlation or convolution. Such a device is for example described in French Pat. No. 73-45234 in the name of Thomson-CSF (publication no.: 2 254 908).
However, the storing and the processing are effected in these devices only in one dimension.
The present invention provides a device for storing analog information at any but distinct points of a two-dimensional surface, and for processing this information, which has the evident advantages of compactness of the device, as well as simplification in carrying out certain types of processing, which will be described below.